Planetary Nebula Abell 84

History

The planetary nebula Abell 84 (PN A55 70, PN A66 84, PK 112-10.1, PN ARO 115) was discovered in 1955 by the American astronomer George Ogden Abell on the photo plates of the «Palomar Observatory Sky Survey» (POSS ) discovered. Most of these 86 PNs discovered on the POSS photo plates are large and have a low surface brightness, which suggests that their stage of development is advanced. Abell described the PN as an asymmetrical ring with bright spots or regions 147x114" in diameter. [331, 332]

Abell 84
Abell 84: Planetary nebula in Cassiopeia; 500 mm Cassegrain 3625 mm f/7.2; SBIG STL11K; 300+90+90+90 min LRGB; Bernese Highlands; © 2015 Radek Chromik
Abell 84
Abell 84: Planetary nebula in Cassiopeia; Takahashi Mewlon 250 CR (2500 mm f/10), SBIG STL 11k; 9L x 1800sec 1×1, 8R, 8G, 8B 2×2 x 1800sec; Bernese Highlands; © 1.9. – 12.9. 2016 Bernhard Blank, Dragan Vogel

Physical Properties

Distances range from 1579 parsecs. The apparent brightnesses in different filters are: B = 18.4 mag, V = 18.6 mag, R = 18.6 mag, I = 18.7 mag. [145]

«Strasbourg-ESO Catalogue of Galactic Planetary Nebulae» Acker et al., 1992 [141]
DesignationsPN G112.9-10.2: A 84, PK 112-10.1, A55 70, ARO 115, VV' 581
Right Ascension (J2000.0)23h 47m 45s
Declination (J2000.0)+51° 23' 58"
Dimensions 120." (optical)
Expansion Velocity 16. km/s (O-III), 25. km/s (N-II)
C-Star DesignationsAG82 458, CSI +51 -23452, UBV 20433
C-Star Magnitude17.67 mag (U filter), 18.67 mag (B filter), 18.49 mag (V filter)
DiscovererABELL 1955

Finder Chart

The planetary nebula Abell 84 is located in the constellation Cassiopeia and is circumpolar for Central Europe. The best time to observe is July to January, when it is highest at night.

Chart Planetary Nebula Abell 84
Planetary Nebula Abell 84 in constellation Cassiopeia. Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

More Objects Nearby (±15°)

References

141Strasbourg-ESO Catalogue of Galactic Planetary Nebulae; A. Acker, F. Ochsenbein, B. Stenholm, R. Tylenda, J. Marcout, C. Schohn; European Southern Observatory; ISBN 3-923524-41-2 (1992); cdsarc.unistra.fr/viz-bin/cat/V/84 (2021-02-18)
145SIMBAD astronomical database; simbad.u-strasbg.fr/simbad
149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
331«Globular Clusters and Planetary Nebulae Discovered on the National Geographic Society-Palomar Observatory Sky Survey» Abell, G. O.; Publications of the Astronomical Society of the Pacific, Vol. 67, No. 397, p.258-261, August 1955; DOI:10.1086/126815; Bibcode:1955PASP...67..258A
332«Properties of Some Old Planetary Nebulae» Abell, G. O.; Astrophysical Journal, vol. 144, p.259, April 1966; DOI:10.1086/148602; Bibcode:1966ApJ...144..259A